Method of vulcanizing wood



(No Model.)

S. E. HASKIN.

METHOD 0F VULUANIZING NYY/'001)l 190.399,199. Pa ted 199.1.5. 1999.

A i c .l i f' @l El byjf/omey N. Permis. mmmmwgnpnw, waging o. r;

UNITED l STATES PATENT @Erica SAMUEL E. HASKIN, OF AVOCA, NEWT YORK.

METHOD OF VULCANVIZING WOOD.

SPECIFICATION forming part of Letters Patent No. 399,196, dated March 5, 1889. Application filed December 5, 1887. Renewed September 29, 1888. Serial lilo. 286,754. (No specimens.l

T LIZ 1111700711, it mf/.y concern: i

Be it known that I, SAMUEL lIAsKIN, of l Avoca, in the county of Steuben and State of l New York, have invented certain new and uset ul Improvements in the Method. ot VulcanizingI ilf'ood; and l do hereby declare the following to be a full, clear, and exact description l5 of the invention, such as will enable others skilled in the art to which it pertains to make and use the same.

My invention relates to an improved method of vuleanizing woodg and it consists in the steps hereinafter described an d claimed.

lleretot'orc in vuicanizing' wood c old air was forced inte the vulcanizingchamber, or so-called "wood-oylluder, until the desired air-pressure was attained, the air in the woodeylinder being heated by coils ot steam-pipe liningI sueh cylinder. 'lhcre were several serious objections to such method. lt the woodcylinder was of practical size*for instance, ot' about eight feet in diameter and from fifty to sixty feet long-a mile or more in length oi steam-pipe was required with which to construct the heating-coils. Such heatingcoils were not only very expensive, but it was almost impossible to prevent the leakage ot steam from some portion of such an extern sive coil, and any leakage of steam in the wood-cylin der was aserious objection, in that the steam discolored and injured the wood beine; treated in the cylinder. lt will be readily understood t-hat an expensive boilerplant was required to furnish steam to supply a coil ot' such large dimensions, and that a high pressure of steam was required to raise and maintain the temperat uresay from 250 to i0@0 or 5000 Fahrenheitaccording to the variety and dimensions of the wood being treated and according to the purposes for which such wood was intended. These, in brief, are some of the difficulties encountered i in vulcanizingI wood with the method hereto fore employed. i

My improved method will be more readily understood by referring to the accompanying drawings. Y

Figure l is a side elevation partly in sec tion, the central portion ot the. wood-cylinder beine` broken away to reduce the size of the drawing. Fig. 2 is an elevation. in transverse section through the wood-cylinder.

A represents the .so-called wood-cylinder, the saine inclosing the vulcanizing-chamber in which the wood is treated. This cylinder may be of any desired size-say about eight feet (more orless) in diameter, and preferably i'rom eighty to a hundred Yi'eet in length. The cylinder is made, preferably, oi' heavy steel plate riveted together, after the manner ot' constructing` steam-boilers, and at least one of the cylinder-heads A must be removable to allow the passage of cars laden with lumber to and from the cylinder. Inside the cylinder are tracks n for the cars u. to travel on. A series ot' cars are employed andthe lumber is piled loosely thereon, and the cars are run into the cylinder, after which the removable head is secured, hernnftically closing; the cylinder.

B is the air-compressor; t, a heater; D, a storage-tank, and E a furnace. The branch F ot' the induction-pipe of the compressor connects with the rear end ot' cylinder A, while the other branch, F', opens into the air, these two branch pipes being provided, respectively, with stop-valves f and f. The eduetion-pipe of the compressorhas a branch pipe, G, leading` direct to tank D, this pipe passing in at the top of the tank and discharging' near the bottoni ot' the tank, substantially as shown, this pipe being` provided with valve g. The other branch, G', of the ed uetion-pipe leads th ro ugh heater C, this pipe being provided with valves g and g2, -arranged on either side of the heater.

Pipe G preferably joins G before reaching` the tank D. By manipulating' the valves of the eduction-pipe the air from the compressor may he discharged directly into tank D, or may be made to pass through heater C on its way to the tank. Heater C is provided with i induction and eduction pipes c and c for the passage of steam to and from the heater, eX- haust-steam beingl usually employed for the purpose, thus utilizing the exhaust ot the engine that drives the compressor and other machinery, which would otherwise be wasted. Tank D is provided with safety-valve D', with glass water-gage d, and with drain-pipe and cock d. The airdiseharge pipe connects at or near the topof the tank, for instance, as

shown. This pipe has a branch, H, leading direct to cylinder A, and connects, prefera- IOO bly, near the front end of the latter, this" pipe being provided with valve 7l. The other branch, H', leads to the furnace E, preferably joining branch H, pipe ll being' provided on either side of the furnace with valves, respectively, 7L and 712, and this pipe being made into a suitable heating-coil where it passes through the furnace. By manipulating these valves the air from tank D may be passed directly to cylinder A, or maybe passed through the coils in the furnace. E on its way to the cylinder. Pipe I leads from the rear end of the cylinder and connects with pipe G, pipe I having a valve, i, and having connected in line thereof a fan-blower, K. Cylinder A is provided with heat and pressure gages and with safety-valve l., of large capacity. Cylinder A, the heater, tank, and pipes, are all jacketed so as to radiate little heat as possible. Cylinder A having been charged and closed as aforesaid, valves f, g, 71., and 'L' are closed and valves f', g', g2, L, and hi are opened and the compressor is set in motion. The air, in passing` through heater C, becomes moderately heated, and in passing through tank D, owing' to the arrangement of pipes as aforesaid, much of the moisture of the air is precipitated, and the water that accumulates is drawn oit from the tank from time to time through pipe d to keep the mouth of pipe G free, the watergage of Vcourse indicating the depth of water inthe tank. The air passing from tank D is superheated in passing through. the coils in the furnace and in such superheated condition is discharged into the cylinder A. The compressor is kept in operation until the desired air-pressure is had in cylinder A. The air introduced into the cylinder during the earlier stages of the process will of course be chilled and greatly reduced in temperature by contact with the cylinder, and more especially by contact with such large quantity ot' lumber. luthis cylinder, so to speak, the pressure should always be kept in advance of the temperatnre-that is to say, the pressure should always be such as to prevent the possibilityv of the sap of the wood boiling or vaporizing under whatever degree of heat is being employed 5 otherwise the boiling of the sap would injure the `liber of the wood, and the sap, being vaporized, would escape from the wood, thus defeating the object in view-lo wil., le retain and vulcanize all of the sap in the wood. lith a compressor of the ample capacity desira-i ble, during the lirst stage ol the process the pressure is likely to be kept considerably in advance of the teimgerature, and under such conditions valve j" may be partially closed and valve f partially opened to give a circulationof air through cylinder A, and cause at least a portion of this air to again pass through the heating-coils of the furnace. Then the compressed air has reached such high temperature that no additional heat will be imparted in the heater during such circulation of the air,

furnace, for the reason that the fan-blower is likely to work better than the compressor with the air at a high temperature. .Meantime, as there are preferably several storagetanks D, only one of which is shown, and

usually only one ata time being used for precipitating the moisture of the compressed air, the compressor may be used to advantage in forcingair into such auxiliary storage-tanks, the pressure in which latter should reach something more than the maximum pressure wanted in cylinder A, so that if it is desired to increase the pressure in cylinder A at any time-for instance, during the latter stage of the process-it maybe done by admitting air from one of these reserved tanks rather than resorting direct to the compressor. lhen such auxiliary storage-tanks are provided and kept charged with compressed air, the air from these tanks may be used to advantage in, lirst, iilling cylinder A, and much time may be saved by such practice over lillin g the cylinder entirely from the compressor. Such auxiliary tanks are all connected in the pipe system substantially like the tank shown, so that` either of them may be used in. connection with heater C and furnace E.

I will remark that it will be better practice to provide a series of small furnaces E with the heating-'coils passing' through the series, rather than relyvon one large furnace, for the reason that one or more such furnaces may be used at a time, as may be required, and the temperature of the air passing through the heating-coils can be better. regulated than with one large furnace. After the woodhas been treated from four hours to twentyefour hours, and subjected meantime to a temperature of from 2250 to 400C or 500" Fahrenheit, according to the variety and dimensions of the wood and the uses for which the wood is intended, cylinder A and contents are cooled down in the following manner: Wlith valV'esf, g', g2, 7L', h2, and 'i closed, and with valves f g, and h open, the compressor is set in motion to force cold air into cylinder A, such air of course passing by the heater and furnace, but passing through tank D for the purpose aforesaid. 'lhe safety-valve. L is set to maintain the maximum pressure had during the vulcanizing process, and the surplus air had by operating the compressor is blown off through valve L. As the temperature in cylinder A becomes reduced, safety-'valve L may from time to time be changed to reduce the pressure, care being had not to reduce the press- IOO IIO

ure below the hoiling-point, so to speak. The operator, having memorized. the table giving the degrees of heatneeessary to reaeh the boiling-point under different pressures, and with the pyronieter and pressure-gage of Cylinder A before him, will have no diiiieulty in cooling down the Wood-cylinder, keeping always such a pressure therein as to preclude the possibility of the sap boiling in the Wood, and when a temperature somewhat below 212C Fahrenheit 'is reached the air-pressure may be dispensed with and the \\'ood-eylin(`ler opened and its contents discharged.

The method herein deserihed marks a radieal advance in the art of vuleanizing wood.

' ln the mattei' of initial oost the apparatus Afor carrying out my improved method is inueh less expensive than the necessary apparatus for carrying out the old method. For iustanee, by dispensing with the heating-oeils in the Wood-cylinder from two to three thousand dollars are saved and the Wood-cylinder is made to Contain. several thousand feet more of lumber. The heatingurnaee and eoils connected therewith are mueh less expensive to eonstruet and operate than the neeessar)v boiler-plant used with the old method. Consideral'ile saving' is effected by using the exhaust-steam of the engine thai drives the eornpresor in heater (l, as aforesaid; also preeipitating the lmoisture of the air in tank l) is found to be oligreat advantage, in this that the qualit-5Y oI the vulcanized product is mueh improved by such praetiee. In the absence ot' heating-Coils in evlinder A the lat-ter is Cooled down in perhaps a third ol the time formerl;Y required.

l. The method herein described of vul eanizing wood, consisting, essentially, inintroducing heated air into the vuleanizingchamber and under sueh pressure as will prevent the evaporation of the sap of the Wood being treated, substantially as set forth.

2. The method herein described of vul eanizing wood, Consisting', essentially, of introdueing heated air into the vuleanizingchamber under sueh pressure as will prevent the evaporation of the sap ol' the wood being treatedf more or less olA the moisture et sueh Compressed air having been precipitated bei'ore the air is discharged into the wood-cylinder, substantially as set forth'.

3. 'lhe method herein described of vuleanizing Wood, consisting', rst, in eompressing air and heating the same; second, preeipi* tat-ing the moist-ure of the air; third, superheating the air land introducing such dry superheated air into the vuleanizing-chamber under sur-h pressure as will preventl the evaporation et the sap of the wood being treated, substantially as set forth.

In testimon)Y whereof l sign this speeieation, in the presence of tivo Witnesses, this lith dav of November, 1887.

SAMUEL E. HASKlN.

\\`"it.nesses: Y

Minnnr E. LvNCH, Cuirs. ll'. Doi-1ER. 

